The present invention relates generally to radiator mechanisms, and more particularly to a radiator mechanism that includes a cooling fan for dissipating heat derived from exoergic circuit components (or heat-producing components) mounted in an electronic apparatus. The present invention is suitable, for example, for a mounting method of the cooling fan for various types of circuit components mounted on a motherboard in a notebook personal computer (PC) or the like.
The motherboard (or main board) in the notebook PC is mounted with the circuit components such as a CPU socket, a variety of memory (sockets), a chipset, an expansion slot, and a BIOS ROM, and directly affects performance and functionality of the PC.
The notebook PCs in recent years tend to include increased number of exoergic components and to generate more calorific values from the various circuit components, as the circuit components mounted on the motherboard provide higher speed and higher performance. Therefore, in order to thermally protect the exoergic components and other circuit components mounted directly or via a socket or the like on the motherboard, the motherboard is provided with a cooler called heat sink.
The heat sink typically includes a cooling (or radiating) fin made up of many high-thermal-conductivity members, and cools exoergic components by spontaneous air cooling. However, the calorific values from exoergic components tend to become too high in recent years to be adjusted by the spontaneous air cooling. Therefore, a fan-cum-heat sink further including a cooling fan has been proposed to enhance a cooling effect of the heat sink. The fan-cum-heat sink provides forced-air cooling to the heat sink utilizing air currents produced by a fan. A conventional fan-cum-heat sink is typically provided above a CPU on the motherboard, as the calorific value from the CPU is the highest among other components.
The cooling fan may be classified into two types: a lateral type that orients perpendicular to one surface of the motherboard; and a longitudinal type that orients parallel with the surface of the motherboard. However, the lateral type is more suitable than the longitudinal type that requires substantial space allocation to a certain thickness for recent notebook PCs required to have a thin (or low-profile) body.
However, the exoergic components are mounted also on a reverse surface of the motherboard opposite to a surface on which the heat sink is mounted. In a conventional embodiment, the calorific values derived from these components are almost negligible, but increased speed and enhanced functionality in recent years have made these calorific values nonnegligible, and influences such as destruction, deterioration, and malfunction due to heat of the exoergic components and other circuit components, thermal deformation of the housing accommodating the motherboard, low temperature burn, and the like have been increasing accordingly. Therefore, the necessity has been arising for the motherboard to be cooled at the both sides (front and back surfaces) in recent years.
To remove the necessity, it would be a conceivable plan to provide cooling fans at the both sides, but this plan would entail increased manufacturing costs, increased power consumption for driving the cooling fans, and increased noise caused by driving the cooling fans.
In this respect, a radiator mechanism that cools both sides of a motherboard using one cooling fan is proposed as disclosed in Japanese Laid-Open Utility Model Application, Publication No. 6-13364. The radiator mechanism 10, as shown in FIG. 7, includes an outer frame 1, a cooling fan 2, fixing tonguelet pieces 3, a connector 4, a motherboard 5, and a connector 6. FIG. 7 is a schematic perspective view of the conventional radiator mechanism 10. The outer frame 1 is fixed in a through hole provided in the motherboard 5 via the fixing pieces 3 and screws (not shown) provided at both sides of the outer frame 1. As a result, the connectors 4 and 6 are electrically connected with each other, and the cooling fan 2 is electrically connected with the motherboard 5.
The cooling fan 2 shown in FIG. 7 has the outer frame 1 embedded in the motherboard 5, and thus may cool the both sides of the motherboard 5 at the same time. In addition, a shift of a mounting position of the fixing pieces 3 provided on the outer frame 1 in an up or down direction to an arbitrary spot would vary a mounting height of the outer frame 1 relative to the motherboard 5, so that a surface generating more calorific value may be effectively cooled.
However, the cooling fan 2 is the longitudinal type, and thus is not suitable for a low-profile notebook PC as described above. Accordingly, a radiator mechanism that can efficiently cool the both sides of the motherboard without preventing the notebook PC from achieving a slim body has been in increasing demand.